Their job is to convert high-voltage alternating current from the mains into low-voltage direct current for mobile phones, laptops, iPods and other electronic gadgets.
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Siemens is also offering high-voltage direct current technology, but ABB is a step ahead.
Its high-voltage direct current system is delivering electricity to the British Petroleum platform in the middle of the ocean.
Power electronics modify the voltage, current or frequency of electricity in applications as diverse as solid-state lighting, intelligent motors and electric vehicles.
One of ABB's specialties is high-voltage direct current links, so-called HVDC.
By combining data from the two steps an equation linking mechanical power (dependent on mass) to electrical power (calculated by multiplying voltage by current) can be derived.
Infineon also provides the thyristor chips that allow transformers to handle high-voltage direct-current power lines.
Large-scale electricity transmission usually uses alternating current, in which both current and voltage oscillate.
It's high-voltage, high-current DC, which is not too far off of automotive electronics from a technology standpoint.
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For example, a system could be injected with current and voltage to see how it would react.
ABB's best trick is its ability to take electric current of any voltage and frequency, chop it up into tiny bits and reassemble it into the form needed.
The resin within the carbon layers is laced with lithium ions, so that each layer acts like an electrode, causing the positively charged lithium ions to collect in one layer when a voltage is applied, and a current to flow when the sandwich is placed in a circuit.
Applying a voltage to the gate determines whether or not current can flow through the channel.
Small changes to the voltage of the grid control large changes in the electron current flowing to the collector plate.
Today AC remains the current of choice, since it converts easily to different voltage levels.
High-voltage DC can carry power over long distances at lower cost than alternating current, but the transformers still cost too much to make the idea widespread.
Lethal electric fences, however, use a continuous current that can make a person lock on to the wire as voltage causes involuntary muscle contractions, paralysis and death.
Electronic chips consist of millions of transistors, each of which does one simple thing: it uses the voltage at one of its three junctions to decide whether or not to let current flow between the other two.
That is the reason why the current emphasis in China is on the construction of 500kv extra-high-voltage lines and long-distance power transmission.
But the central point about both taps and transistors is that they allow a small signal the twist of a hand or the increase of a voltage to control a much larger one the rush of water or of electrical current.
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